Dielectric and optical constants of λ-Ti3O5 film measured by spectroscopic ellipsometry

A thin film of lambda-trititanium pentoxide (λ-Ti3O5) was prepared by sintering titanium dioxide nanoparticles on a quartz substrate. The dielectric constants of the real (ε′) and the imaginary (ε″) parts, the optical constants of the refraction index (n), and the extinction coefficient (k) for λ-Ti3O5 were determined by spectroscopic ellipsometry. The optical transitions of λ-Ti3O5 are attributed to the electronic transitions due to the free electron carrier and the oxygen-to-metal charge transfer band.